Microsoft released its next-generation Windows Server "Longhorn" software for public testing on Wednesday and said the product is on track for a debut in the second half of 2007. The company said it expects hundreds of thousands of information technology workers to download the Beta 3 version of the next server operating system code-named Longhorn. Longhorn, which will replace the current Windows Server 2003, is the server operating system equivalent of Microsoft's new Windows Vista PC operating system with an emphasis on many of the same features such as better security. The download is available at www.microsoft.com/getbeta3.